new widget: Adjust Clock (BETA)

For my "Advanced PPM" I recorded temperature and drift at multiple stable temperatures and then calculated needed quadratic equation from those datapoints.

While it would be possible for widget to automatically follow temperature and detect when temperature has remained stable long enough, problem is that GPS only works outside and so you can't use e.g. freezer for stable cold temperature, or room temperature for another datapoint as I did.

I don't see how user would be able to get the needed datapoints at multiple stable temperatures with GPS.

(I guess it might be possible to calculate needed quadratic equation without stable temperatures but my math skills aren't enough for that.)